Safety locking device for casings



March 6, 1928.

B. H. SMITH SAFETY LOCKING DEVICE FOR CASINGS Filed April 2, 1925 INVENTOR.

I 33% gm lrwrr 7301 4! f/ J/WI/b Patented Mar. 6, 1928.

UNITED STATES 1,661,272 PATENT OFFICE.

BOYD H. SMITH, OF SHELBY, OHIO, ASSIG-NOR TO THE AUTOCALL COMPANY, OF SHELBY, OHIO, A CORPORATION OF OHIO.

SAFETY LOCKING DEVICE FOR CASINGS.

Application filed April 2, 1925.

This invention, as indicated, relates to a safety locking device for a casing. More par- ,icularly it comprises a casing frame adapted to be seated upon abase plate and to be moved laterally to permit the locking of the same. It also includes means for closing a tamper switch in circuit with a recording mechanism whereby the removal and replacement of said cover will be indicated upon such recording mechanism.

The principal object of the present invention is to provide an improved locking device for securing a casing frame to the base plate; Another object is to provide said casing frame with means co-acting with a switch mechanism supported on the base plate which will indicate when said casing is removed or replaced. Other objects of the invention will appear in the course of the following description. To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims.

The annexed drawing and the following description set forth in detail certain mechanism embodying the invention, such disclosed means constituting, however, but one of various mechanical forms in which the principle of the invention may be used.

In said annexed drawing Fig. 1 is a top plan view showing a structure embodying the principles of the invention; Fig. 2 is a vertical sectional view taken along the line 22 shown in Fig. 1, looking in the direction of the arrows; Fig. 3 is an enlarged detail view, partially in section, taken along the line 3-3 shown in Fig. 2, looking in the direction of the arrows; Fig. 4c is a vertical sectional view showing the locking mechanism; Fig. 5 is a perspective view showing in enlarged detail the under side of the collar which forms part of the locking means upon the base member; and Fig. 6 is an enlarged vertical sectional view of a tamper switch mechanism, taken along the line 6-6 shown in Fig. 1, looking in the direction of the arrows.

As is clearly shown in the drawing, the casing 1, adapted to enclose and protect the article for which it forms a cover, is provided at its lower edge with a frame 2 carrying plates 3 adapted to fit over and interlock with posts 4 supported at spaced intervals upon a base plate 5.

Serial No. 20,307.

The base plate and cover illustrated are intended particularly to enclose a record ing apparatus wherein code records are marked upon a record strip, but obviously the invention is not restricted to use with a casing for any particular purpose but may be used with an enclosure wherever constructions of neat appearance, providing for engagement between the frame and the base plate are found desirable, and also where co-operation with an indicating device to show whether or not such casing has been tampered with is an advantage.

The casing illustrated preferably has an upper portion formed entirely of plate glass, with the lower edges 6 of the side walls thereof received within grooves 7 formed in the upper edges of the frame members 2 and cushioned by means of lining material 8 of suitable character. The corner plates 3 are received in notched-out seats so as to leave their under faces flush with the lower edge of said frame. The corner plates, as shown, are of square shape, with their inner corners cut away at the point where they overhang the space within the casing. The outer edges of said plates are secured to the under side of the frame by means of screws 9, or other .suitable fastening elements. In the projecting portions of said plates, adjacent the meeting edges of the frame, circular openings 11 are provided which are adapted to fit over the posts 4 and inter lock with the same.

The posts 4 may be formed in various ways, but as illustrated, comprise collars 12 having cylindrical body portions and having a portion adjacent their base cut away at one side of the axial opening so as to provide a base portion of elliptical outline and of somewhat smaller area than the cylin-' drical upper portion. Said collars are seated upon the upper portions of screws 14, the. lower screw-threaded ends 15 of which are engaged within screw-threaded apertures 16 formed adjacent the respective corners of the base member. The collars are turned with their cut away portions facing toward the rearward end of the base plate, which is the portion shown adjacent the top of the sheet of drawing in Fig. 1. Thus, the cut away portions of the collars form locking shoulders at the rearward edges of each of the posts, and when the circular apertures in the corner plates are engaged over the heads lift sin I. i l "1 ll of said posts, the bodily movement of the casing toward the front of the base board will bring the corner plates adjacent said apertures beneath said shoulders and securely interlock the same with said posts so that the casing may not be removed therefrom in an upward direction.

lfn order to prevent the shifting of the casing rearwardly upon the base: plate to disengaging position, means for locking said casing to the base plate is provided. he is more clearly shown in Fig. l of the drawing, such means comprises a barrel type lock 21, which is secured centrally to the forwarr i member of the casing frame and is provided upon its rearward end with a laterally extending locking plate 22 adapted,- when said barrel is rotated upon its axis, to be brought into engagement with a pin 23 of short length set into the base plate adjacent the front edge and spaced therefrom a sufficient distance to bring said pin rearwardly of the inner face of the locking plate of said lock when the casing is in interlocked position upon the posts. 7

ft will be obvious that when thelockingij plate is engaged in front of said pin it will be impossible to remove the casing from the base plate.

Adjacent the rearward portion of the base plate, at a point immediately in ront of the position occupiedby the 'rezrward frame memberof the casing, a tamper switch 25 is provided. Said tamper switch comprises a block 26 of insulating inaterial, having a central recess 27 within which a pair of spring contact arms 28, 29, are adapted to extend. 'lhe uppermost of said :contact arms is of somewhat greater length than the lowermost arm and the forward end thereof is engaged in a slot 31 formed in the switch shaft 32 of said tamper switch. rdaid switch shaft is engaged in a transvere opening in said insulating block which intersects one end of the central recess thereof. The switch shaftis made of short length to permit sliding movement in the body of the switch block above the upper portion of said base plate. The upper end of the switch shaft is rounded and is adapted to be engaged by the inner extension 34; of an angle bracket 35 suitably secured to the inner face of the rearward member of the casing frame.

Vi hen the casing frame is in position the switch shaft will be held downwardly, with its upper end in the plane of the upper face of the insulating block. When the casing is removed from the base plate the switch shaft will be projected upwardly a slight distance above the top of. the insulating block through the action of the spring contact arm when the circuit is opened.

Upon the upper side of theinsul ting block, a sliding key. 36 is provided, said hey earers having an upturned rearward end adapted to be engaged by the rearward edge of the angle bracket upon the casing frame. The key is provided with an elongated slot 3'7 within which the body portions of the retaining screws 38 are engaged. When the key is moved rearwardlyupon the insulating block it will ride over the rounded upper end of the switch shaft and depress the same to close the contact arms. When in such position, if the casing is restored to the base plate, the projecting flange of the angle plate 34f will come into contact with the 'inclined portion of the key and will move the same rearwardly vupon the switch block. Thus, as the sliding lrey moved away from the head of the switch shaft, the :contacts will be momentarily opened, producing a punch record, before the projecting portion of the angle plate comes directly into contact with the head of the switch shaft tO-again close said contacts.

@ther modes of applying the principle of my invention may beemployed instead of the one explained, change being made. as regards the mechanism herein discloserhprovided the means statedby any of the fol lowing claims or the equivalent of such stated means be employed.

ll therefore particularly pointout' and distinctly claim as my invention:

1. an apparatus of the character descriliied, having in combinations base plate, a plurality of posts secured to said base plate having cut away portions formed at the rearward sides thereof, a casing frame, plate Secured to said frame and adapted to seat over said posts and to engage with the cut away portions thereof, means to prevent disengagement of said frame from said, posts, a tamper switch mounted on said base plate, and means carried by said frame for operating said tamper switch.

2. An apparatus of the character described, having in combination a base plate, a plurality ofposts secured 'tOzSEtldblSQ plate having cut away portions formed at the rearward sides thereof, a .:casing, frame, plates secured to said frame and adapted .to seat over said posts andtoen 'age with the cut away portions thereof, means to prevent disengagement of said frame from said posts, a tamper switch mounted on said base plate, and a bracket carried by said frame for operating said tamper switch when said frame-is engaged with said post 3. an apparatus of the character described, having in combination a base'plate, a pluralityof posts secured to said'base plate having cut away portions formed at the rearward sides thereof, a casing frame plates secured to said frame and adapted toseat over said posts and to engage with ithecut away portions thereof, means to prevent disengagement of said frame from said posts, a

tamper switch block mounted on said base plate, a pair of spring contact arms enclosed in said block, a switch shaft slidably engaged in said block and normally held with its upper end projecting from said block, and a bracket on said frame for, depressing said shaft and bringing said arms into contact with each other when said frame is engaged with said posts.

4-. An apparatus of the character described, having in combination a base plate, a plurality of posts secured to said base plate having cut away portions formed at the rearward sides thereof, a casing frame, plates secured to said frame and adapted to seat over said posts and to engage with the cut away portions thereof, means to prevent disengagement of said frame from said posts, a tamper switch block mounted on said base plate, pair of spring contact arms enclosed in said block, a switch shaft slidably engaged in said block and normally held with its upper end projecting from said block, and a key slidably mounted on the upper face of said block and adapted to be moved over the projecting end of said shaft to depress the same and bring said. arms into contact with each other.

5. An apparatus of the character described, having in combination a base plate, a plurality of posts secured to said base plate having cut away portions formed at the rearward sides thereof, a casing frame, plates secured to said frame and adapted to seat over said posts and to engage with the cut away portions thereof, means to prevent disengagement of said frame from said posts, a tamper switch block mounted on said base plate, switch arms mounted within said block, a switch shaft slidably engaged in said block, and means carried by said frame for co-operating with said switch shaft to control the action of said tamper switch.

6. An apparatus of the character described, having in combination a baseplate,

a plurality of posts secured to said base plate having cut away portions formed at the rearward sides thereof, a casing frame, plates secured to said frame and adapted to seat over said posts and to engage with the cut away portions thereof, means to prevent disengagement of said frame from said posts, a tamper switch block mounted on said base plate, switch arms mounted within said block, a switch shaft slidably engaged in said block, means carried by said frame for co-operating with said switch shaft to control the action of said tamper switch, and a key slidably mounted on said block and adapted to co-operate with the switch shaft to control the action of said tamper switch when said casing frame is removed from said base plate.

7. An apparatus of the character described, having in combination a base plate, a plurality of corner posts secured to said base plate having cut away portions formed at the rearward sides thereof, a casing frame, corner plates secured to the respective inner corners of said frame and adapted to seat over said corner posts and to engage with the cut away portions thereof, means to prevent disengagement of said frame from said posts, a tamper switch block mounted on said base plate adjacent the rearward portion of said frame, a pair of spring contact arms enclosed in said block, a switch shaft slidably engaged in said block and normally held with its upper end projecting from said block, a key slidably mounted on the upper face of said block and adapted to be moved over the projecting end of said shaft to depress the same and bring said arms into contact with each other, and a bracket on said frame adapted to move said key rearwardly and seat over the upper end of said switch shaft to hold the switch arms in contact with said posts.

Signed by me, this 7th day of March, 1925.

BOYD H. SMITH. 

